Question

1.3 Tính hợp lý: a) 4524 - (864 - 999) - (36 + 3999) c) - 329 + (15 - 101) - (25 - 440) 1.4 Tìm số nguyên x, biết: a) (x + 43) - 43 = 37 c) - (x - 23) - 223 = 114 b) 1000 - (137 + 572) + (263 - 291) d) -3752-(29-3632)-51. b) 234 - (x - 234) = - 112 d) - 41 - (- 141 + x) = 34

Answer 1

1.3.

a) \(4524-\left(864-999\right)-\left(36+3999\right)\)

\(=4524-864+999-36-3999\)

\(=4524-\left(864+36\right)-\left(3999-999\right)\)

\(=4524-900-3000\)

\(=3624-3000\)

\(=624\)

c) \(-329+\left(15-101\right)-\left(25-440\right)\)

\(=-329+15-101-25+440\)

\(=\left(-329-101\right)+\left(15-25\right)+440\)

\(=-430-10+440\)

\(=-440+440\)

\(=0\)

Answer 2

1.4.

a) \(\left(x+43\right)-43=37\)

\(x+43-43=37\)

\(x+0=37\)

\(x=37\)

b) \(234-\left(x-234\right)=-112\)

\(x-234=234-\left(-112\right)\)

\(x-234=346\)

\(x=346+234\)

\(x=580\)

d) \(-41-\left(-141+x\right)=34\)

\(-141+x=-41-34\)

\(-141+x=-75\)

\(x=-75-\left(-141\right)\)

\(x=66\)